摘要：
Long-term intake of thermally processed starch-based foods may impact glucose homeostasis, but the consistency of the effects of various thermal treatments and the reasons are not clear. In this study, thermal treatments, especially boiling, damaged the crystal structure and inter-molecular hydrogen bonds of starch-based blends, thus decreasing the structural order and stability. These thermally treated starch-based blends increased the appetite of mice, promoted food digestion, and enhanced postprandial glucose response. Normal C57BL/6J mice were treated with boiled, baked, and fried starch-based diets for ten weeks. Compared to the baked and fried starch-based diets, the boiled starch-based diet significantly (p <0.05) elevated random blood glucose levels and disrupted insulin homeostasis, primarily due to the remarkable decrease in gut microbial diversity. Both baked and fried starch-based diets resulted in relatively high intestinal epithelial permeability (plasma lipopolysaccharide increased by 28.67% and 21.85%, respectively). They adversely affected islet beta-cell function and evoked glucose metabolism disorder. Overall, results demonstrate a clear connection among the thermal processing of starch-based diets, disruption of intestinal homeostasis, and adverse glucose metabolism. This study lays a theoretical foundation for the formulation of food processing strategies to mitigate the adverse effects of thermally treated food on glucose homeostasis.
作者机构：
[Tian, Yaoqi; Ma, Rongrong; Liu, Chang] State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China;[Tian, Yaoqi; Ma, Rongrong; Liu, Chang] School of Food Science and Technology, Jiangnan University, Wuxi 214122, China;[Shen, Wangyang] School of Food Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China;[Tian, Yaoqi] Analysis and Testing Center, Jiangnan University, Wuxi 214122, China. Electronic address: yqtian@jiangnan.edu.cn
通讯机构：
[Yaoqi Tian] S;State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China<&wdkj&>School of Food Science and Technology, Jiangnan University, Wuxi 214122, China<&wdkj&>Analysis and Testing Center, Jiangnan University, Wuxi 214122, China
摘要：
Total starch granule-associated proteins (tGAP), including granule-channel (GCP) and granule-surface proteins (GSP), alter the physicochemical properties of starches. Quinoa starch (QS) acts as an effective emulsifier in Pickering emulsion. However, the correlation between the tGAP and the emulsifying capacity of QS at different scales remains unclear. Herein, GCP and tGAP were selectively removed from QS, namely QS-C and QS-A. Results indicated that the loss of tGAP increased the water permeability and hydrophilicity of the starch particles. Mesoscopically, removing tGAP decreased the diffusion rate and interfacial viscous modulus. Particularly, GSP had a more profound impact on the interfacial modulus than GCP. Microscopically and macroscopically, the loss of tGAP endowed QS with weakened emulsifying ability in terms of emulsions with larger droplet size and diminished rheological properties. Collectively, this work demonstrated that tGAP played an important role in the structural and interfacial properties of QS molecules and the stability of QS-stabilized emulsions.
关键词：
small-angle X-ray scattering;starch;radius of gyration
摘要：
Starch retrogradation is a complex process involving changes in the multi-scale structure. In particular, the particle order of retrograded starch is unclear. In this study, we measured the radius of gyration (Rg) and radius of particles (R) of retrograded starch using small-angle X-ray scattering. Retrograded starch included various Rg, and the values of Rg depended on the length and state of the starch chains. With time, the standard deviations of R decreased due to the increase in particle uniformity. Based on these results, a new method for assessing the degree of starch retrogradation was established from the perspective of the particle order. The accuracy of the new method was verified through differential scanning calorimetry and scanning electron microscopy. The microstructures of the samples indicated that the retrograded starch granules contained substructures (primary particles) of different sizes. This study provides a new perspective for analyzing the structure of retrograded starch.
期刊：
现代食品科技,2022年38(2):197-205 and 86 ISSN：1673-9078
通讯作者：
Shen, W.
作者机构：
[陈璁; 沈汪洋] School of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, 430023, China;[程世伦] Zhongxiang Xingli Foods Co. Ltd., Jingmen, 431900, China;[叶爽] School of Biological Engineering and Food, Hubei University of Technology, Wuhan, 430064, China;[史德芳; 范秀芝; 殷朝敏; 姚芬; 高虹] National Research and Development Center for Edible Fungi Processing, Institute of Agricultural Products Processing and Nuclear-Agricultural Technology, Hubei Academy of Agricultural Sciences, Hubei Provincial Engineering Research Center of Under-forest Economy, Wuhan, 430064, China
通讯机构：
School of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
关键词：
Assembling behavior;Electrostatic interaction;Particles motion;Protein/Polysaccharide complex;Pulsed electric field
摘要：
Pulsed electric field (PEF) could change the charge distribution of proteins and polysaccharides and affect their interactions and complexes aggregation, but those influences are not enough evaluated. Here, the effects of PEF on the complexes of alpha-amylase and pectin driven by electrostatic binding were studied. Changes in molecular conformation of alpha-amylase and assembly structure of alpha-amylase/pectin complexes were orderly assessed by fluorescence, FTIR, DSC, enzyme activities, particle size, zeta-potential, CLSM, and SEM. After PEF treatment (E similar to 20 kV/cm, t(exp)similar to 1 ms, and 5 cycles), the intrinsic fluorescence of alpha-amylase was quenched, the content of beta-sheet increased, enzyme activities lose almost 80%, and the denatured temperature increased. Zeta-potential of alpha-amylase/pectin complexes did not change significantly, but the particle size rose gradually. The particle revolution of alpha-amylase/pectin complexes was recorded by Turbiscan, and the size growth model fit the Allometric function well. Finally, the complexes of alpha-amylase and pectin after PEF treatment tended to the branched, ring, or circles-like shape.
